A.B. Shugart, witness for the prosecution, walked along the edging of a small, tree-lined park in Denver on the morning of May 5th, 1911. From within those trees there echoed a gunshot. On a patch of grass 300 feet away Shugart spotted two figures: A man, on his hands and knees; and standing over him a woman, pistol in hand. According to his testimony, Shugart cried out for the woman to stop, saw the gun fire again and the man drop to his stomach. The woman then knelt and tucked the murder weapon under her victim and fled into the door of a nearby house. Running over to the scene of the crime, Shugart lifted the head of the man, only to find him already dead. Shugart turned and ran to the home he had seen the woman disappear into where he found her slouched in a chair, dazed. Immediately he searched her for additional weapons and, finding none, asked who the man outside was.

“He is my husband,” the woman said. “He wronged me.”

The trial that followed would consume the entire nation, later becoming one of Colorado’s most bizarre and controversial true stories.

The defendant in the case was Gertrude Gibson Patterson. Newspapers called her “The most beautiful woman in America.” The district attorney called her “A vile vampire.”

Chicago, 1900

Born to a poor Illinois family in 1881 and expelled from school at 13, Gertrude eloped to Chicago with a saloonkeeper. When her father tracked her down and brought her home, Gertrude only ran back to the city, this time with the wealthy clothing manufacturer Emil W. Strouss.

Nearly forty years her senior, Strouss was smitten with the young and beautiful Ms. Gibson, and after appealing to her father was eventually allowed to be the girl’s benefactor – a formal title that assumedly granted Strouss other, more sensual privileges.

Still, Strouss saw to it that Gertrude was afforded the best in aristocratic society. She traveled the world with him, studying four years in Paris and becoming fluent in French.

Years later, upon returning to Chicago, Gertrude met and fell in love with a poor but handsome former football player named Charles A. Patterson. Although Strouss had for years wanted to marry her, Gertrude chose instead to abscond to California with Charles. Both the secret marriage and honeymoon were financed by Gertrude’s regular allowance from Strouss.

Only later did Gertrude admit to her patron her relationship with Charles. Strouss, now well along in years and apparently understanding, kept Gertrude under his wing with her now acting as his interpreter on his regular trips to Europe.

Gertrude’s young husband was meanwhile trying his own hand in entrepreneurship. But after one failed business after another decided simply to live off of Gertrude’s money from Strouss. After a severe bout of pneumonia however, Charles contracted tuberculosis and was forced to relocate to Denver in order to recover in a sanitarium under Colorado’s dryer climate.

Denver, 1898

Now apart, Gertrude’s and Charles’ marriage started to crumble. Charles became fiercely jealous of Gertrude’s relationship with Strouss. He began to demand increasingly more money from her. He grew abusive and, according to Gertrude, would regularly beat her during her trips to visit him in the sanitarium. It was only when she learned her husband had filed a $25,000 suit against Strouss for “alienation of the affections of his wife” that Gertrude decided upon a divorce.

She left for Denver, set on finalizing the divorce, and rented a small bungalow apartment not far from Charles’ sanitarium. What happened next sent newspaper reporters rushing in from around the country.

According to the prosecution, the morning of the murder Gertrude telephoned the sanitarium in hopes of arranging a meeting with her husband. But when Charles’ refused, Gertrude instead stalked to a park by the sanitarium and hunkered down near a pathway her husband was known to regularly walk.

“When Patterson finally appeared and saw his wife,” said prosecutor Horace Benson, “we expect to show that he started to run, but stood still when his wife called to him to stop; that a witness who heard the first shot saw Patterson on his hands and knees and heard him cry out; that this witness saw Mrs. Patterson standing over him; that the witness cried out to her not to shoot; that Mrs. Patterson shot her husband again in the back, and that a moment later the witness saw her shove the revolver under her husband’s body and flee into the E.B. Hendrie home.”

It appeared an open and shut case. The murder was pre-meditated, unprovoked. “It’s thirty of Gertie,” proclaimed one newspaper. “[She] used her beauty to enslave and destroy,” said the defense attorney, “and should be hanged by the neck until dead for the crime of shooting her lawfully wedded husband, the saintly and consumptive Charles Patterson.”

It was then, moments before closing arguments and a seemingly sealed fate for Gertrude that the defense introduced a last-minute, surprise witness. The prosecution was shocked. Sworn in, the man proceeded to inform the court how he, traveling through town on his way to Wyoming, had stayed in a local hotel the night before the murder. That morning, while walking to a late breakfast, he had overheard an intense argument in a nearby park. Following the noise, the man was stunned to see a man suddenly slap the defendant, then violently throw her to the ground. It was only then, in desperate self-defense, that said defendant revealed a gun and fired into the back of the assailant just as he was turning. He claimed that once the man had fallen that he had “wanted no part of this at the time, so walked quickly away…. But I saw enough. The woman’s life was in danger.”

This final account still resonating in their ears and almost certainly touching off all chivalrous instincts in the all-male jury, the jury deliberated, only to quickly return. The verdict: Not guilty.

The prosecution was in disbelief. “If we cannot convict a murderer on the evidence we presented, what is required in the way of truth and fact to convict?” one member said. Almost immediately a great speculation arose surrounding the court’s decision and this mysterious surprise witness. One reporter claimed seeing the man later leave his Denver hotel pocketing a large wad of cash. Another person claimed to having witnessed Gertrude receiving a bulky letter addressed from Strouss, a letter reportedly stuffed with cash. The prosecution would later hire a detective agency to investigate this last witness, but the man was never found.

According to a later article in the Denver Post, “more than the jurors chivalry may have been aroused. At least four of the male jurors visited Gertrude in her hotel room after the trial. One, who brought flowers, seemed especially eager to get into Gertrude’ s, good graces.”

Following her acquittal, Gertrude fled the attention of the press for Europe. Here accounts of her final years vary. Some claim that after lying low in Europe for a few years Gertrude returned to the U.S. and married a judge in Rockford, IL. But other articles from the time assert that the woman killer who had captivated the media never did see her home country again after having boarded a return ship with a destiny all its own: The Titanic.